f a roller-coaster car has 60,000 J of gravitational potential energy when at rest on the top of a hill, how much kinetic energy does it have when it is ¾ of the way down the hill so only ¼ of the track is left?

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If an astronaut takes an object to the moon the following is true (choose only one). a the mass will change but the weight will be the same. b both the mass and the weight of the object will be the same. c the weight will change but the mass will be the same. d both the mass and the weight of the object will change.

In which type of system is power held solely by the central government and not shared with regional governments? group of answer choices federal unitary confederate oligarchic